Cannot set LD_LIBRARY_PATH in /etc/profile.d

Question

I have installed nVidia CUDA 7.5 in Ubuntu Mate 16.04. However, I am having trouble setting up the environment variables.

Here is the nvidia-settings.sh file that I have in /etc/profile.d folder:

export PATH=/usr/local/cuda-7.5/bin:$PATH
export LD_LIBRARY_PATH=/usr/local/cuda-7.5/lib64:/usr/lib/nvidia-361:$LD_LIBRARY_PATH
export LIBRARY_PATH=/usr/lib/nvidia-361:/usr/local/cuda-7.5/lib64:$LIBRARY_PATH

However, after reboot the LD_LIBRARY_PATH environment was not automatically available. Here is the terminal output that shows the issue:

ponir@mate:~$ echo $LD_LIBRARY_PATH

ponir@mate:~$ echo $LIBRARY_PATH
/usr/lib/nvidia-361:/usr/local/cuda-7.5/lib64:
ponir@mate:~$ export LD_LIBRARY_PATH=/usr/local/cuda-7.5/lib64:/usr/lib/nvidia-361:$LD_LIBRARY_PATH
ponir@mate:~$ echo $LD_LIBRARY_PATH
/usr/local/cuda-7.5/lib64:/usr/lib/nvidia-361:
ponir@mate:~$ 

But after executing export LD_LIBRARY_PATH=/usr/local/cuda-7.5/lib64:/usr/lib/nvidia-361:$LD_LIBRARY_PATH in Terminal I could get that variable.

What could be the issue? Thanks.

Solution

From Ubuntu wiki help page

Note: You can only set this environment variable inside an interactive shell. [ie a terminal ] Since Ubuntu 9.04 Jaunty Jackalope, LD_LIBRARY_PATH cannot be set in $HOME/.profile, /etc/profile, nor /etc/environment files. You must use /etc/ld.so.conf.d/*.conf configuration files. See Launchpad bug #366728 for more information.

How to fix it:

cd /etc/ld.so.conf.d

Make a file with the .conf extension here

sudo nano cuda.conf

Add the paths to it as two lines

/usr/local/cuda-7.5/lib64
/usr/lib/nvidia-361

Save and exit. Check with ls -l that the file has the same ownership and permissions as others in the directory, they should be:

-rw-r--r-- 1 root root

Then run

ldconfig

This doesn't set the env variable, but includes the libraries appropriately so CUDA works

Comments

[edwinksl]

You should have done echo $LD_LIBRARY_PATH and echo $LIBRARY_PATH to see if these two environment variables exist.

[ponir]

echo $LD_LIBRARY_PATH gives a blank output as well.

[edwinksl]

Can you update your question with the output from using echo? That removes the "No such file or directory" noise that is distracting us from the core of your question.

[ponir]

I have recreated the issue in a new terminal and this time using echo. I have updated the question. I think there is something wrong in my nvidia-settings.sh file. But cannot figure out what!

[ponir]

I do remember setting up LD_LIBRARY_PATH in Ubuntu 14.04. And it worked there. The problem with ldconfig is that it gives an error with libcudnn.so.4 files (cuDNN v4): /sbin/ldconfig.real: /usr/local/cuda-7.5/lib64/libcudnn.so.4 is not a symbolic link as these are non standard library. And packages need LD_LIBRARY_PATH variable in order to load cuDNN.

[Zanna]

You should be able to fix that error from ldconfig : see here @ponir